Uppror Media Group
By radiating the power in the direction of choice, Electronically Switched Directional (ESD) antennas can reduce network contention and avoid packet loss. There exists some ESD antennas for wireless sensor networks, but so far researchers have mainly evaluated their directionality. There are no studies regarding the link dynamics of ESD antennas, in particular not for indoor deployments and other scenarios where nodes are not necessarily in line of sight. The authors' long-term experiments confirm that previous findings that have demonstrated the dependence of angle-of-arrival on channel frequency also hold for directional transmissions with ESD antennas.